Background Arts
The present invention relates to a semiconductor device, and in particular, a semiconductor device including a test circuit, a semiconductor chip, and a test method for a semiconductor chip.
Background Arts
Prior to shipping, semiconductor devices are tested in order to confirm whether or not a desired output signal is outputted from an output terminal when a prescribed signal is applied to an input terminal. When performing the test, a probe needle is placed in contact with a pad that is connected to each output terminal of the semiconductor device, and the output signal is acquired through the probe needle, for example.
In the case of semiconductor devices with a large number of output terminals such as driver ICs for display panels, in order to mitigate an increase in IC chip area resulting from the increase in the number of output terminals, it is desirable for the space between adjacent pads to be narrowed.
In such a case, when the space between adjacent pads is narrowed, it becomes difficult to cause the probe needle to contact each pad in a manner such that the probe needles do not interfere with each other. In order to solve this problem, a semiconductor device was proposed in which a switching circuit for extracting in an alternating fashion the signals of the pads connected to the respective output terminals, and a test pad were further provided, and each signal selected by the switching circuit was outputted from the test pad (see, for example, Japanese Patent Application Laid-Open Publication No. 2003-163246). According to this configuration, during testing, the probe needle need only be in contact with the test pad of the semiconductor device, and thus, it is possible for the probe needle to be reliably connected to the test pad even if the space between the pads is narrow.